GcFree, Inc. is founded on recent discoveries and patents about a sialic acid called Neu5Gc, which is present in large amounts on the surface of cells of most animals, but not humans. Potentially immunogenic Neu5Gc from exogenous sources (e.g., animal- derived reagents used for making biotherapeutic products) are taken up by human cells and expressed on their surfaces, as if produced within those cells. Thus, Neu5Gc frequently contaminates biopharmaceutical products, as well as human cells cultured for therapeutic use. Meanwhile, all humans also have circulating antibodies against Neu5Gc, some at very high levels. Thus, the presence of Neu5Gc could result in reduced efficacy, immune rejection or even immune responses against therapeutic cells or drugs. Neu5Gc is also being ingested and incorporated into the human body from dietary sources, primarily from red meats and milk products. Furthermore, various human diseases associated with eating red meat and milk products (particularly heart attacks, strokes, several common cancers, and possibly autoimmune diseases) could be triggered by the combination of having the Neu5Gc antigen and the anti-Neu5Gc antibodies present in the same human body. This newly founded company focuses on many commercial opportunities related to critical human health issues arising from these discoveries. This particular grant focuses on detecting Neu5Gc in all biotherapeutic applications and in normal and pathological human tissues. Thus, we propose to optimize production and specificity of polyclonal antibodies for detecting and measuring Neu5Gc in biotechnology and biomedical research applications;and develop mouse monoclonal antibodies for detecting and measuring the full spectrum of specific Neu5Gc- containing epitopes. Phase 1 will include commercialization of the polyclonal antibodies and Phase 2 proposes to generate additional human and/or humanized monoclonal antibodies, and to complete the commercialization of all products. This research effort will impact public health to leading to products designed to detect and prevent foreign Neu5Gc -incorporation phenomenon . This phenomenon is likely to be of practical biomedical relevance, because the lab has found that all humans also have antibodies against Neu5Gc circulating in their blood. Thus, the presence of immunoreactive Neu5Gc on cultured cells and biopharmaceuticals intended for human use is likely to result in reduced efficacy, immune rejection or even serious immune responses against the therapeutic cells or drugs